I see you found the problem - as you found out, the VRM products are very hungry for system resources, it's best if you have them installed on a dedicated PC and keep it off the internet for everything other than Windows updates and that sort of stuff.
As for shutting things down, there's a program called End-It-All that will do that for you in only one or two steps, you can get it here
. I use it just before launching FX, works like a charm - it even shuts down the anti-virus scanner.
Other tweaks can be found in this thread
, although those tweaks are for XP. I don't have any systems running Vista so I don't know if any of them apply to Vista.
Good luck and welcome to the forum.
*EDIT* for additional info - if your music is on your internal drive, you may want to consider moving it to an external drive, especially with the VRM products - that was another cure for a stutter problem I had in the very beginning.